This Small Business Innovation Research Phase I project will determine the feasibility of a new immunoassay system based on an ultra-sensitive magnetic detector and stable, non-toxic, magnetic labels. Such a system has the potential to provide a very sensitive assay in a homogeneous format. The homogeneous format and short measurement times, would increase throughput significantly and reduce assay costs. The novel magnetic detection system will take advantage of recent breakthroughs in high-temperature (high-Tc) SQUID sensors. We intend to fabricate these sensors and incorporate them into a test-bed platform in order to quantify the limits of the detection and assess the benefits of the technique. We will then conduct a "head-to-head comparison" of the sensitivity of the proposed technique against an established ELISA assay for the detection of corticotropin-releasing factor (CRF). In Phase II, we will develop a prototype instrument with improved sensitivity and multi-sample measurement capability and we will demonstrate the suitability of this new technique in other immunoassay formats as well as DNA probes. PROPOSED COMMERCIAL APPLICATIONS: Our goal is develop a bench-top magnetic immunoassay detector to meet the needs of research and clinical laboratories where high sensitivity is required and existing techniques are limited by cost, throughput, sensitivity, or toxicity. While the initial instrument to be developed is targeted at a sizable research market, this new immunoassay system has potential to compete in many segments of the much larger ($5 billion/year world-wide) commercial clinical market. In addition the sensitivity of this technology may ultimately allow us to perform DNA analysis without performing a PCR amplification step and would find significant commercial and research application.